This application is directed to a microwave oven and an improved microwave energy seal for a microwave oven.
A problem in microwave ovens is to maintain the leakage of energy from the microwave oven cavity during operation thereof below the maximum levels established by state and federal regulatory agencies. While currently marketed ovens employ energy seal structures capable of meeting these requirements, there is a continuing desire on the part of manufacturers to improve upon the current seal arrangements and thereby substantially exceed these government standards.
One arrangement known in the art for sealing a microwave oven enclosure employs the generalized teachings of microwave choke structures known for some time in the microwave communication art. An example of such a teaching is U.S. Pat. No. 2,772,402 which is directed to a microwave energy enclosing structure for providing a substantial electric junction between conductive members spaced a small distance apart, thereby inhibiting electrical leakage therefrom. This patent teaches the use, for this purpose, of slots or discontinuities in one conductive member to suppress the propagation of microwave energy longitudinally along the conductive members (generally perpendicular to the direction of the slots). The conductive members in such an arrangement are spaced apart a distance much smaller than the one-quarter wavelength of the microwave energy employed in the system. The lengths of the slots are selected to be approximately an odd multiple of a quarter wavelength (preferably one-quarter wavelength), with the width of the slots being appreciably smaller than one-quarter wavelength and several times smaller than the length thereof. The other conductive surface is preferably continuous, but may alternatively be provided with a slotted configuration.
U.S. Pat. No. 3,767,884 discloses energy sealing structure adapted for use in the microwave oven art which employ a slotted plate similar to the type disclosed in U.S. Pat. No. 2,772,402 and incorporate this slotted plate feature into the more generalized choke arrangement disclosed in U.S. Pat. No. 3,767,884.